Most of the “cascading effects” of global climate change will be felt in the region, including increased air temperature, decreased precipitation in some areas, and more severe storms. Along the West Coast, oceans will become more acidic and warm and sea level will rise.

The draft plan outlines the potential impacts to region in unequivocal language.

In the mountains of the West, the EPA projects that Most ecosystems will slowly migrate and shift their distribution towards the north in response to warming temperatures. But alpine areas are often distributed as small and isolated areas surrounded by other habitats, and they can be disconnected from each other by wide stretches of land used for other purposes, including timber production, ranching and agriculture.

Instead of shifts in latitude, alpine vegetation and animals will be limited to shifts in altitude, unless connections between suitable habitats can be made. Global warming will mean that lower elevation habitats will shift into higher zones and encroach on alpine and subalpine habitats. At the same time, high-elevation plants and animals will lose habitat — some will simply disappear off the tops of mountains.

Changes in the timing and amount of runoff, which have already been documented. That will affect the availability of freshwater, with earlier melting leading to drier conditions for the balance of the water year, and the potential for increased fire frequency and intensity.

According to the EPA, impacts to water supplies are the region’s major vulnerability, and the agency proposes to help communities adapt by doing more to promoting water efficiency, conservation and recycling. Protecting and restoring wetlands could also help buffer the impacts of climate change to groundwater and surface water supplies.

Other adaptation strategies could include more green infrastructure for more sustainable stormwater management by reducing polluted runoff to surface waters.

The agency’s draft climate change adaptation implementation plans are open for public comment. The plans, and links for comments are at this EPA website.